In communications systems, a mechanical, electro-mechanical, or electronic device for making, breaking, or changing the connections in or among circuits. 2.Deprecated synonym forcentral office, switching center.3. In communications systems, to transfer a connection from one circuit to another.4. In a computer program, a conditional instruction and a flag that is interrogated by the instruction. 5. In a computer program, a parameter that controls branching and that is bound, prior to the branch point being reached. Synonym switchpoint. 6. In computer programming, a programming technique or statement for making a selection, such as a conditional jump. 7. In computer software applications, a functional unit, such as a toggle button, used to make selections.